Eric G. Davis, 34, was booked this week at the Pasco County jail to face charges that he beat Joe Hayes, 54, with his bare fists while the two were housed at the Zephyrhills state prison. He is being held without bail until his arraignment before Circuit Judge Pat Siracusa on a charge of non-premeditated homicide.

The Polk County Medical Examiner said Hayes — who died April 21, 2012, at Lakeland Regional Hospital — died of multiple injuries caused by blunt force trauma. For the past year, the Florida Department of Corrections would not release details about the circumstances surrounding Hayes' death. The agency has declined public records requests from the Tampa Bay Times.

Family members said one ear was black and swollen, and he had bruises on his face and arm.

Hayes, whose occupation was listed as a hospital orderly, was serving a 99-year prison term for a series of burglaries and rapes in 1980 in Charlotte County.

A judge sentenced Davis to life without parole after a jury convicted him of second-degree murder in the March 1, 2006, shooting of 26-year-old Krystal Lee Davis, his wife and the mother of four children, including two she had with Davis.

According to authorities, Davis, who was 27 at the time, shot Krystal in their duplex in Safety Harbor. She had recently told him she was seeing someone else.

Defense attorney Edward Liebling argued that Davis was mentally ill. But Assistant State Attorney Robin Augello asked that Davis be put away for life because he was dangerous and had not shown remorse. In a letter Davis wrote to a friend, Davis said he enjoyed seeing the crime scene pictures during trial, Augello said.

"He's probably as close to a monster as we are going to find," Augello said during the trial.